Process for recovering potassium compounds from waste gases of cement kilns or the like.



H. BLUMENBERG, Ja- PROCESS FOR RECOVERING POTASSIUM COMPOUNDS raom WASTE GASES or CEMENT KILNS on THE LIKE.

APPLICATION FILED MAY 20, I9").

Patented Mar. 4,1919.

. -31 "li I rnoonss For. moovnnmc POTASSIUM COMPOUNDS FROM; warrants-assassin! mLns on. THE LIKE.

UN TED STATES PATENT OFFICE. l v .r. ,ao w aps' V ,1, I 1 y n a HENRY'BLUMENBERG, JR, 01? 0B0 GRANDE, CALIFORNIA, .assxanon. rocnnilglg 011 :1 a... ce-K M cous'rauc'rrozv coMrANY, or Los A GELES, CALIFOBNITLJ-IQ?(103280354? CALIFORNIA.

To all whom at may camera: -i

,.B.e it known that I, HENRY BLUMENIBERG, Jr., a citizen of the United States, residing; at Oro Grande, in the county of San Bernardin and State of California, have invented new and useful- Improveni nts in Processes for Recovering Patassiur Compounds from Waste Gases of Cemen Kilns or the like, of which the following is a specification.

My invention relates to a process of rec ering potassium compounds from waste gases.

In cement kilns that operate with potassium containing raw materials and produce potassium salts as a by-product, the waste gases are subjected to various treatments in order to recover or extract the potassium compounds carried thereby. Where hailie towers are used in which water or a salt solution is sprayed and contacted with the hot gases, it is necessary to retard the flow of the r to providea sufficient number of be e towers in order to recover substantially ail the potassium compounds.

I have discovered that the potassium compounds may be easily extracted from the gases by subjecting them to a preliminary washing and cooling, saturating them with aqueous vapor and cooling them to approximately the freezing point of water. The condensation of the aqueous vapor on condensin will precipitate all the solid matter carried in said gases, including the potassium compounds which may be separated from the constituents of the aqueous solution by the usual methods.

My invention consists in the steps of the process hereinafter described and claimed.

In the accompanying drawings which form a part of this s ecification I have shown an apparatus suitable for carrying on my process, and in which:

Figure 1 is a vertical section thereof.

2 is a, horizontal section taken on the line 2-2 of Fig. 1.

Referring to the drawings, 10 indicates the upper end of a cement kiln which is in communication with a conduit 11 leading to a series of dust collecting and cooling chambers 12, 13 and 14 but v ich may consist of any desired number. 'hese heating S ecification of Letters Patent.

P ent as Application filed May 20,1918. Serial-.No.235,722. "I

' chambers communicate with means of passagesformed respectivelgriiii i u it Q amines,

HE" a the vertic bathe walls; 15 and lfi-arran'g in staggered relation as clearl shown.- iuii n m1," u'f a; 33* hos mash We: are beans} Fig. 2. 17, x18 and 19 arc'suita le doors diva the side walls of the dust collecting-chain bers' through which the-collected dust may be removed; A passa e 20 leads from the last chamber 14 into a afiie'or preci 'tating tower 21 provided with horizonta perforated bafiie plates 22. 23 is a centrifugal pump for clrculating water by means of pipe 24 and spray nozzle 25 throu h the precipitating tower 21. The li ui collected in the inclined bottom 26 of t e preci itating tower 21 is returned by means 0 pipe 27 to the pump 23. When the Water has collected a suificient amount of cement dust containing potassium compounds, so that the resulting magma or slurry is handled with difficulty by the pump 23, it is pumped into a series of evaporating pans 28, 29 and 30 by means of a branch pipe 31 leading from pipe 24 and which is provided wit a valve 32. 34 is a valve in the pipe 24 which is closed when the valve 32 is opened to divert the slurry into said pans. 35, 36 and 37 are valved outlet pipes leading from the branch pipe 31 into evaporating pans 28, 29 and 30, respectively. Each pan is provided with valved outlets 38 through which the slurry after the desired degree of concentration has been reached is allowed to flow into the dust collecting chambers 12 13 and 14.

The gases after passing through the precipitating tower 21 are drawn through conduit 39 by means of a blower or fan 40 into the lower part of the refrigerator 41 where the rest of the cement dust and otassium compound is recovered. The re rigerator 41 is provided with a central cooling portion consisting of a condenser 42 through which a series of spaced vertical pipes 43 open at both ends are arranged. The cooling medium preferably brine, of a tempera- .ture considerably below the 32 F. is,ad-

the cooling of the aqueous vapor which on passing through the pipes 43 are condensed. The condensation of the aqueous vapor forms a fog which collects all the dust particles carried in suspension by the gases, and the condensed water containin the dust and potassium compounds is co ected in the bottom of the refrigerator 41 whence the same is run through a valved outlet pipe 46 into an evaporatingpan 47 provided with a suitable steam coil48. Here the mixture -is concentrated and potassium compounds may be se arated' from the other constituents of the mixture by the usual methods.

The essential feature of this invention is ases which have been subjected as descri ed to a preliminar washing and cooling to a temperature pre erably not above 40 F. whereby, throu h the condensation of the aqueous vapor, the remaining potassium compounds carried by the gases are recovered.

I claim: c

A process of recovering potassium compounds from the Waste gases of cement kilns and the like, comprising subjecting said gases to a preliminary cooling of 200 F.

and saturating the same with an aqueous vapor, and cooling said gases to about 40 F., by passing them through a refrigerating zone, whereby the aqueous vapor is condensed and collects the potassium compounds.

, In testimony whereof I have'signed name to this specification.

HENRY BLUMENBERG, JR. 

